Once a socket is locked on a clip, the clip can be moved along the rail. Clips can be added to or removed from the rail without removing the other clips/sockets.
Since the clips just slide on/off the rails, or can be popped on/off between other clips, the rails can be customized with 1/4" and 3/8" and 1/2" drive clips.
Another thing, rails do not have to be placed on the mounting kits. Clips can be placed on both sides of the rails, saving lots of space as the sockets will then lay flat.
Obviously, as my setup demonstrates, I'm not worried about footprint. And to get sockets on/off a clip requires only 1/8 twist. There is no mechanism in the dura-pro clip to break. As the pics show, the rails can hold socket extensions, socket adaptors, swivel sockets, and wrenches.
If I take a rail off the mount and carry it to the work, I can lay it down without everything falling off and there is no tray to collect a bunch of dust and dirt.